X-Git-Url: https://git.ozlabs.org/?a=blobdiff_plain;f=pppd%2Fsys-linux.c;h=df5cebb55951cfa8960ee3f8f2686d9f9a8caa99;hb=431469a02ce74e5fe4b9943e86b9bfc272882fcb;hp=6e1423808458c32f61e57293fdfcd486fffaeb29;hpb=61821b9b6106a1e834ce14783a0b03b8c5301328;p=ppp.git

diff --git a/pppd/sys-linux.c b/pppd/sys-linux.c
index 6e14238..df5cebb 100644
--- a/pppd/sys-linux.c
+++ b/pppd/sys-linux.c
@@ -2101,10 +2101,43 @@ get_if_hwaddr(u_char *addr, char *name)
  * get_first_ethernet - return the name of the first ethernet-style
  * interface on this system.
  */
+static char first_ether_name[IF_NAMESIZE];
 char *
 get_first_ethernet(void)
 {
-	return "eth0";
+	struct if_nameindex *if_ni, *i;
+	struct ifreq ifreq;
+	int ret, sock_fd;
+
+	sock_fd = socket(AF_INET, SOCK_DGRAM, 0);
+	if (sock_fd < 0)
+		return NULL;
+
+	if_ni = if_nameindex();
+	if (!if_ni) {
+		close(sock_fd);
+		return NULL;
+	}
+
+	first_ether_name[0] = 0;
+
+	for (i = if_ni; !(i->if_index == 0 && i->if_name == NULL); i++) {
+		memset(&ifreq.ifr_hwaddr, 0, sizeof(struct sockaddr));
+		strlcpy(ifreq.ifr_name, i->if_name, sizeof(ifreq.ifr_name));
+		ret = ioctl(sock_fd, SIOCGIFHWADDR, &ifreq);
+		if (ret >= 0 && ifreq.ifr_hwaddr.sa_family == ARPHRD_ETHER) {
+			strlcpy(first_ether_name, i->if_name, sizeof(first_ether_name));
+			break;
+		}
+	}
+
+	if_freenameindex(if_ni);
+	close(sock_fd);
+
+	if (!first_ether_name[0])
+		return NULL;
+
+	return first_ether_name;
 }
 
 /********************************************************************